Upper Extremity Levels of Amputation

Amputation of DigitsGenerally the level will be determined by the degree of injury. If the upper extremity injury is solely to the index or little finger, useful function is unlikely unless one and a half phalanges are still present. Even at this level initial acceptance of this limited loss by the patient is often transmuted into a desire for cosmesis and later amputation is requested. The best cosmesis is achieved by amputation through the metacarpal shaft with suitable beveling. This, however, reduces the span of the hand and power of the grip and it may be better in larger manual workers to amputate through the metacarpophalangeal joint. The long and ring fingers are best amputated through whatever level will leave a mobile and comfortable stump. Even a very short stump, for example the proximal phalanx, may have some definite functional value and in the half-closed position be at least cosmetically acceptable. Amputations of either of these fingers in which the metatarsal ray is excised for cosmetic reasons may seriously disturb function and are seldom desirable. As much of the thumb as can be must be preserved for as long as possible. Any stump covered with sensitive skin may be of great value.Wrist disarticulationIndications for wrist disarticulation are rare but usually related to severe trauma to the hand with considerable loss of tissue and loss of sensation. Any tissue with sensation should be preserved. Even carpal bones and remnants of metacarpals, providing they are covered by viable skin, may be useful as the wrist extensors and flexor may be preserved as well.Shoulder disarticulationThe arm completely lost​The ForearmThe usual indications for amputation through the forearm are for severe trauma affecting the wrist and hand and occasionally it is used as treatment for chronic sepsis or tumor of the hand. Ideally as with other amputations, the stump should be as long as possible. A too distal amputation, however, whilst having the advantage of a long lever and ease of fitting, often suffers from cold and cyanotic skin with little subcutaneous and muscular tissue covering the bone ends. Therefore the ideal distance is 17cm measured from the olecranon in the average adult and this roughly corresponds to the junction of the proximal two-thirds and the distal one-third of the forearm. Occasionally the extent of the trauma or disease affecting the hand and forearm may be too great to allow a useful below-elbow stump to be fashioned. In the past conventional treatment would have been to amputate at the level of the distal humerus but as a result of the recent improvements in prosthetic design, disarticulation at the elbow is preferable. It looks as though it will be possible, by retaining the bulbous stump, to have a self-retaining socket and a better joint in the future. Technique. The skin flaps will often be determined by whatever skin is available but where possible equal anterior and posterior flaps should be made the incisions beginning at the level of the humeral epicondyles and extending distally 4 cm beyond the point of the olecranon posteriorly and to point just distal to the insertion of the biceps anteriorly.

Forequarter AmputationClavicle, scapula, and arm are excised. This amputation is rarely performed and is indicated only for malignant tumors around the shoulder joint, particularly where the tumor has spread into the surrounding muscles so that the less mutilating procedures of disarticulated of the shoulder or amputation through the neck of the humerus are no longer practicable.Amputation through the HumerusThe commonest indication is severe trauma of the forearm. Occasionally this amputation may be used for sepsis or malignant tumors As elsewhere in the upper limb the level may be determined by factors beyond the surgeon’s control. The ideal is 10cm above the elbow joint, which leaves room for the elbow mechanism in the prosthesis and provides the best length of stump for fitting. Above this level as long a stump as possible should be retained.Amputation through the Neck of the HumerusThis operation does not leave the patient with any functional stump and should not be performed when it is possible to leave a humeral stump extending to three finger breadths below the anterior axillary fold. This is the critical minimal length to which an upper limb. Prosthesis can be fitted. If the amputation is being performed for malignant tumor at the lower end of the humerus there is no alternative but disarticulation at the shoulder joint. To leave the humeral head in site when it is permitted on pathological grounds, however, produces a better cosmetic appearance, particularly when wearing clothes, by preserving the rounded contour of the shoulder.